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onsemi BC639RL1
- Part No.:
- BC639RL1
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-226-3, TO-92-3 Long Body, Formed Leads
- Datasheet:
-
BC639RL1.pdf
- Description:
- TRANS NPN 80V 1A TO92
- Quantity:
- Payment:
- Shipping:
Inventory:9,857
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Product details
Overview
BC639RL1 from ON Semiconductor is an NPN silicon high-current transistor in TO-92 package, rated for 80 VCEO, 1.0 A continuous collector current, and 625 mW power dissipation at TA = 25°C. It delivers hFE ≥ 40 at IC = 150 mA and supports switching and linear amplification in low-voltage power control circuits.
For engineers reviewing the BC639RL1 datasheet, pinout, applications, or equivalent options, key selection factors include its 80 V breakdown rating, 1.0 A DC current capability, TO-92 thermal resistance (RJA = 200 °C/W), and verified performance in relay drivers and LED ballasts under industrial ambient conditions.
Technical Context
The BC639RL1 operates as a general-purpose NPN bipolar junction transistor optimized for medium-power switching and analog amplification. Its design targets stable DC current gain (hFE = 40–160) across IC = 5 mA to 500 mA, with VCE(sat) ≤ 0.5 V at IC/IB = 10 and fT = 200 MHz for RF-adjacent signal handling.
Thermal management relies on TO-92 case construction with RJC = 83.3 °C/W and RJA = 200 °C/W, requiring heatsinking or airflow for sustained >500 mA operation. The device is not rated for automotive or medical use per ON Semiconductor's safety disclaimer.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 80 V - Maximum collector-emitter voltage before breakdown; enables use in 48 V industrial bus and 24 V relay driver stages. |
| IC (continuous) | 1.0 A - Sustained collector current capacity; supports solenoid loads up to 12 W at 12 V with adequate heatsinking. |
| hFE | 40–160 - DC current gain range at IC = 150 mA and VCE = 2 V; ensures reliable base drive sizing for switch saturation. |
| VCE(sat) | ≤ 0.5 V - Low saturation voltage at IC = 500 mA/IB = 50 mA; limits conduction loss to <250 mW in switching mode. |
| fT | 200 MHz - Current-gain bandwidth product at IC = 50 mA/VCE = 2 V; supports audio-frequency amplification and fast-switching PWM control. |
| RJA | 200 °C/W - Junction-to-ambient thermal resistance; requires PCB copper area ≥ 1.5 cm² or forced air for >300 mA continuous duty. |
Pinout & Package
BC639RL1 uses the standard TO-92 (Case 29, Style 14) plastic package with 3 leads. Pin 1 is Emitter, Pin 2 is Collector, Pin 3 is Base - confirmed by ON Semiconductor marking diagram and package outline.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Emitter) | Current exit path | Connected to ground or low-side return; determines polarity of bias network and current-sense placement. |
| 2 (Collector) | Current entry path | Drives load between supply rail and collector; must withstand full VCEO during off-state transients. |
| 3 (Base) | Control input | Receives current-limited drive (typically 5–50 mA); base resistor value set using hFE min and required IC. |
Key Features
| Feature | Design Value |
|---|---|
| Pb-free option available | BC639RL1G variant meets RoHS Directive 2011/65/EU without lead-based solder compatibility compromises. |
| High VCEO rating | 80 V allows direct interface with 48 V telecom supplies and 36 V battery systems without external clamping. |
| Low VCE(sat) | ≤ 0.5 V at IC/IB = 10 reduces power loss and self-heating in high-duty-cycle switching applications. |
| Stable hFE over current range | hFE remains ≥ 40 from 5 mA to 500 mA, simplifying base drive design across load variations. |
Applications
| DC Motor Driver Stage | LED Constant-Current Ballast |
|---|---|
Use Scenario: Driving 12 V, 800 mA brushed DC motors in industrial actuators with PWM-controlled speed regulation. IC Role / Device Role / Timing Role: NPN switch controlling motor current path between 12 V rail and ground; base driven by microcontroller GPIO via current-limiting resistor. Use Value: VCE(sat) ≤ 0.5 V limits conduction loss to <400 mW, enabling operation without heatsink at 50% duty cycle. | Use Scenario: Regulating current through high-brightness white LEDs in signage backlighting with 24 V input. IC Role / Device Role / Timing Role: Linear current regulator with emitter resistor feedback; collector tied to 24 V, emitter to LED string cathode. Use Value: hFE stability ensures ±10% current accuracy across temperature, supporting consistent luminance without digital compensation. |
| Relay Coil Driver | Audio Preamp Stage |
Use Scenario: Energizing 24 V, 400 Ω relay coils in PLC I/O modules requiring galvanic isolation and surge tolerance. IC Role / Device Role / Timing Role: High-gain switch turning coil current on/off; flyback diode connected across coil to clamp inductive kick. Use Value: 80 V VCEO safely absorbs 100+ V flyback spikes without avalanche stress or secondary protection. | Use Scenario: Low-noise voltage amplifier stage for electret microphone signals in voice-recognition edge devices. IC Role / Device Role / Timing Role: Common-emitter small-signal amplifier with bypassed emitter resistor; biased at IC ≈ 1 mA for optimal fT-noise trade-off. Use Value: fT = 200 MHz provides >10× headroom above 20 kHz audio band, ensuring flat gain response and minimal phase distortion. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar NPN transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BC639ZL1 | Same electrical specs and TO-92 package; differs only in packaging format (ammo box vs. tape & reel). | No functional difference; selected when bulk manual assembly or non-automated pick-and-place is used. | Choose BC639ZL1 for hand-soldering or low-volume prototyping where tape-and-reel feed is unnecessary. |
| MPSA42 | Higher VCEO = 300 V but lower IC = 500 mA and hFE = 25–100; TO-92 package with same pinout (E-C-B). | Better suited for high-voltage, low-current applications like CRT deflection or snubber circuits; less ideal for >600 mA loads. | Select MPSA42 only when VCEO > 100 V is mandatory and load current stays below 400 mA. |
Compared with BC639RL1, BC639ZL1 offers identical electrical behavior with alternate logistics packaging, while MPSA42 trades current capacity for higher voltage tolerance-making BC639RL1 preferable for 24–48 V, sub-1 A power switching where gain consistency and low saturation loss are critical.
Availability
BC639RL1 is available at Aetrix Electronics and suitable for relay drivers, LED ballasts, and DC motor control circuits requiring stable component supply, long-term manufacturability, and RoHS-compliant sourcing.
Supply support for BC639RL1 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
ON Semiconductor (now part of onsemi) is a global semiconductor supplier focused on energy-efficient electronics, with core expertise in power management, analog, and discrete devices.
The BC639RL1 belongs to the BC63x family of high-current NPN transistors designed for cost-sensitive industrial and consumer power control applications where reliability, thermal robustness, and standardized TO-92 compatibility are essential.
FAQ
What is the maximum collector-emitter voltage rating for BC639RL1?
The BC639RL1 has a maximum collector-emitter voltage (VCEO) rating of 80 Vdc, as specified in the ON Semiconductor datasheet under Maximum Ratings. This rating applies at IC = 10 Adc with IB = 0 and defines the upper limit for safe operation in switching or linear modes. Exceeding this voltage risks irreversible breakdown, especially under transient conditions without clamping.
Does BC639RL1 support surface-mount assembly?
No, BC639RL1 uses the through-hole TO-92 package (Case 29, Style 14) with three axial leads and is not compatible with standard SMT reflow processes. It requires wave soldering or hand soldering. For surface-mount equivalents, consider SOT-23 packages like MMBT4401, though those differ in voltage, current, and gain specifications versus BC639RL1.
What is the typical DC current gain (hFE) of BC639RL1 at 150 mA collector current?
The BC639RL1 exhibits a minimum hFE of 40 at IC = 150 mA and VCE = 2.0 Vdc, with typical values reaching 100–160 depending on unit variation and temperature. This gain range is confirmed in the Electrical Characteristics table and supports predictable base resistor calculation for saturation switching in designs using BC639RL1.
Is BC639RL1 suitable for automotive applications?
No, BC639RL1 is not qualified for automotive use. ON Semiconductor explicitly states that its BC63x series devices are not designed, intended, or authorized for use in systems supporting or sustaining life-including automotive safety-critical functions. The BC639RL1 lacks AEC-Q101 qualification and operates within −55°C to +150°C junction range, but does not meet automotive reliability or testing requirements.
How does the thermal resistance of BC639RL1 affect PCB layout?
With RJA = 200 °C/W, BC639RL1 requires careful thermal design: a minimum 1.5 cm² copper pour connected to the emitter pad significantly reduces junction temperature rise. Without added copper or airflow, power dissipation above 312 mW (at ΔT = 62.5°C) risks exceeding the 150°C max junction temperature. Layouts using BC639RL1 should avoid narrow traces and isolate heat-generating components nearby.
BC639RL1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-226-3, TO-92-3 Long Body, Formed Leads
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Transistor Type:
- NPN
- Current - Collector (Ic) (Max):
- 1 A
- Voltage - Collector Emitter Breakdown (Max):
- 80 V
- Vce Saturation (Max) @ Ib, Ic:
- 500mV @ 50mA, 500mA
- Current - Collector Cutoff (Max):
- 100nA (ICBO)
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 40 @ 150mA, 2V
- Power - Max:
- 625 mW
- Frequency - Transition:
- 200MHz
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TO-92 (TO-226)
BC639RL1 FAQ
1.How can I place an order for BC639RL1 through Aetrix?
Please submit a Request for Quotation (RFQ) for BC639RL1 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for BC639RL1 reliable?
The price and inventory of BC639RL1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC639RL1 is usually 5 days.
3.What payment methods are accepted for BC639RL1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC639RL1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC639RL1?
BC639RL1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC639RL1 order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for BC639RL1?
For technical support, including BC639RL1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC639RL1 requirements.
6.How does Aetrix verify that BC639RL1 is sourced from the original manufacturer or authorized distributors?
All BC639RL1 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that BC639RL1 meets industry standards.
7.What is the process for return or replacement of BC639RL1?
All BC639RL1 units undergo pre-shipment inspection (PSI). If there is an issue with BC639RL1, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The BC639RL1 part is unused and in its original packaging.
Return procedure for BC639RL1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC639RL1 Tags
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Nexperia USA Inc.
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